U.S. patent number 4,372,631 [Application Number 06/308,146] was granted by the patent office on 1983-02-08 for foldable drafting table with drawers.
Invention is credited to Harry I. Leon.
United States Patent |
4,372,631 |
Leon |
February 8, 1983 |
Foldable drafting table with drawers
Abstract
A lightweight drafting table having a full-size drafting board
of sandwich-type construction, the underside of which is glued to a
yoke having three support arms which are disposed approximately
parallel to each other and which are connected to a cross member to
form a rigid structure for supporting two drawers. The board
provides the cover for the drawers when they are closed. Each
drawer has a slot formed in each of two sides thereof; the walls of
each slot ride on a key which protrudes laterally from one of the
support arms. A slight drag between the key and the slot prevents
each drawer from opening under the force of gravity alone when the
drafting board and the drawer are tilted at an angle of several
degrees to the horizontal and the drawer is fully loaded. The yoke
is pinned to a pair of vertical support members attached to a
four-legged base and to a pair of braces, each of which is also
bolted to one of the support members to form a lightweight
structure of exceptional strength. Several bolt holes are provided
in each brace so that the angle of the board to the horizontal can
be readily adjusted. With casters fitted to the base and the board
folded nearly parallel to the vertical support members, the
drafting table can be moved readily from one room to another by a
single operator or stored in a small space.
Inventors: |
Leon; Harry I. (Atlanta,
GA) |
Family
ID: |
23192751 |
Appl.
No.: |
06/308,146 |
Filed: |
October 5, 1981 |
Current U.S.
Class: |
312/231; 108/6;
108/8; 312/233; D6/656.11 |
Current CPC
Class: |
A47B
27/02 (20130101) |
Current International
Class: |
A47B
27/00 (20060101); A47B 27/02 (20060101); A47B
027/00 (); A47F 005/12 () |
Field of
Search: |
;312/231,333
;108/6,8,9,26 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
273667 |
|
Feb 1951 |
|
CH |
|
1123146 |
|
Aug 1968 |
|
GB |
|
Primary Examiner: Sakron; Victor N.
Attorney, Agent or Firm: Leon; V. L.
Claims
What is claimed is:
1. A drafting table which comprises:
(a) a board;
(b) at least one pair of support arms which are attached to the
underside of the board, the support arms being spaced apart from,
and disposed generally parallel to, each other; and
(c) a drawer which is insertable between the pair of support arms;
each support arm having first slot and key means cooperating with
second slot and key means on the drawer for supporting the drawer
beneath the board, even when the drawer is tilted at an angle of
several degrees from the horizontal,
(d) said first slot and key means further comprises at least one
pair of keys and a pair of stays, each stay protruding from one of
the support arms on a side thereof to which one of the keys is
connected; each stay and the key proximate thereto being spaced
apart, the opposing walls thereof being disposed generally parallel
to each other; and (e) said second slot and key means further
comprises a pair of slots formed in the sides of each drawer and
segments of the drawer disposed between each slot and the proximate
upper edge of the drawer, each key cooperating with a slot as at
least one of said segments cooperates with a pair of opposing
walls, so that drag forces between a key and the slot with which it
cooperates are augmented by interaction between a segment and at
least one of the opposing walls proximate thereto, thereby braking
movement of the drawer under the force of gravity alone.
2. A drafting table according to claim 1 which further comprises a
pair of vertical support members, each of which is pivotally
connected to a portion of a support arm reinforced by the key
connected thereto, so that the drafting table can be folded into a
unit of narrow width to facilitate its transport.
3. A drafting table which comprises:
(a) a board;
(b) a pair of support arms which are connected to the underside of
the board, the support arms being spaced apart from, and disposed
generally parallel to, each other; a pair of keys, each key being
rigidly connected to one of the support arms; the lengths of each
support arm and the key connected thereto being substantially
equal; each key having at least two recesses formed therein, the
section of the support arm which is contiguous to each recess
having one hole which communicates therewith;
(c) a pair of vertical support members, each member being connected
to one of the support arms near its mid-section;
(d) a pair of braces, one end of each brace being connected to one
of the vertical support members, the other end of each brace being
connected to one of the support arms; and
(e) at least two pins, one of which connects each support arm to
one of the vertical support members and the other of which connects
each support arm to one of the braces, portions of each pin being
disposed within one of the recesses and the hole proximate thereto,
thereby forming a pair of three-sided structures for supporting the
board.
4. A drafting table which comprises:
(a) a board;
(b) at least one pair of support arms which are connected to the
underside of the board, the support arms being spaced apart from,
and disposed generally parallel to, each other;
(c) a pair of vertical support members; at least one pin which
connects each support arm to one of the vertical support
members;
(d) at least one drawer which is insertable between the pair of
support arms; each support arm having a key which cooperates with a
slot on the drawer for supporting it beneath the board; and
(e) the keys being disposed generally parallel to each other, each
key having at least one recess formed therein, the recess being
disposed substantially within a section of each key which protrudes
from the support arm to which it is connected; the portion of the
support arm which is contiguous to the key having a hole which
communicates with the recess, the head of the pin being disposed
entirely within the recess when the body of the pin is inserted
into the hole, so that the pin does not interfere with the motion
of the drawer along the way.
5. A drafting table according to claims 3 or 4 wherein the board is
further characterized as having two thin faces of hardwood and a
core structure of corrugated fiberboard, the faces being separated
from each other by the core structure.
6. A drafting table according to claims 3 or 4 which further
comprises:
(a) a cover sheet; and
(b) a plurality of molding sections formed of a non-metallic
material, one of which is secured to each of the narrow sides of
the board, each molding section extending upwardly along
substantially the entire length of the side of the board to which
it is secured, the top surface of the molding section being
disposed generally upwardly of the drafting board a distance which
is at least as great as the thickness of the cover sheet, thereby
substantially eliminating the snagging of the cover sheet by a
drafting instrument.
7. A drafting table according to claims 1 or 4 which further
comprises the drawer having means projecting from the rear side
thereof for engaging a catch means secured to the board; the
projecting means being releasable from the catch means when a force
substantially in excess of gravity alone acting on the drawer is
applied to the front thereof to pull it away from the catch means,
so that the drawer can be maintained in a closed position when the
board is tilted downwardly at a steep angle to the horizontal.
8. In an apparatus having a structure to which a pair of support
arms are connected, the support arms being spaced apart from, and
disposed generally parallel to, each other, the structure having at
least one opening into which a drawer is insertable, the
improvement comprising:
(a) at least one side of each support arm having a key and a stay
protruding therefrom, the stay and the key proximate thereto being
spaced apart, the opposing walls thereof being disposed generally
parallel to each other; and
(b) the drawer having a pair of slots formed in the sides thereof,
each key cooperating with a slot; a segment of the drawer disposed
between each slot and the proximate upper edge of the drawer
cooperating with said opposing walls, the upper end of the segment
riding against a stay as each key rides against a section of the
sides of the slot with which it cooperates whenever the front of
the drawer begins to rotate downwardly with respect to a plane
which generally bisects the opening into upper and lower portions,
thereby braking the movement of the drawer under the force of
gravity alone.
9. An apparatus according to claim 8 which further comprises the
drawer having means projecting from the rear side thereof for
engaging a catch means connected to the structure; the projecting
means being releasable from the catch means when a force
substantially in excess of gravity alone acting on the drawer is
applied to the front thereof to pull it away from the catch means.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to drafting tables of the type having a
single pair of vertical support members about which the drafting
board can be pivoted.
2. Description of the Prior Art
A drafting table in the prior art comprises a drafting board
supported at an angle above a four-legged table or desk which has
its own top in addition to the drafting board. Drawers for storing
drafting supplies are either supported beneath the top of the
four-legged table or are included in a separate piece of furniture.
In the former arrangement, the drawers tend to obstruct the
movement of the draftsperson's legs, especially when the
draftsperson is sitting upon a drafting chair having an elevated
seat. Placement of the drawers in a separate table or desk, on the
other hand, consumes floor space. Moreover, mobility, which is
restricted by the fact that the drafting table alone tends to be
heavy and bulky in order to eliminate any relative movement between
the drafting board and its support structure, is further hampered
by the addition of yet another piece of furniture.
SUMMARY OF THE INVENTION
The principal object of the present invention is to improve the
construction of drafting tables of the type discussed above by
providing at least two support arms which are disposed
approximately parallel to each other and which are attached to the
underside of a lightweight drafting board of sandwich-type
construction to form a rigid structure for supporting at least one
drawer. The drafting board covers the drawer when it is closed,
thus eliminating the need for a table top and providing ample
clearance between the drawer and the floor for the movement of a
draftsperson's legs. Moreover, with the drawer supported directly
beneath the board, the drafting table can be folded rapidly into a
unit of narrow width to facilitate its transport.
A key formed in each support arm is insertable into a slot formed
in the contiguous side of the drawer, the drawer being slidable
along the key. A slight drag between the key and the slot prevents
the drawer from opening under the force of gravity alone when the
drafting board and the drawer are tilted at an angle of several
degrees to the horizontal and the drawer is fully loaded.
A further object is to provide a pair of light-weight, three-sided,
pinned structures of exceptional strength for supporting a drafting
board, each structure comprising a support arm, a vertical support
member, and a brace. The pin connecting each support arm and
vertical support member as well as the pin connecting each support
arm and brace extend through openings formed in the key in the
support arm and in the contiguous portion thereof. The heads of the
pins are recessed beneath the surface of the key so that they do
not interfere with the motion of the drawer along the key.
Molding which rises above the top surface of the drafting board a
slight distance, which is approximately equal to the thickness of a
vinyl cover sheet, is attached to the sides of the board to reduce
the incidence with which the cover sheet becomes snagged by a
drafting instrument and pulled away from the surface of the
board.
Another object is to provide a drafting table which can be easily
disassembled for shipment and reassembled thereafter, all of the
various components of the drafting table being of such dimensions
that they can be packaged together within a thin shipping container
having a thickness of approximately 8 inches and a width and length
slightly greater than the corresponding dimensions of the drafting
board.
BRIEF DESCRIPTION OF THE DRAWINGS
Further details are explained below with the help of the examples
illustrated in the attached drawings in which:
FIG. 1 is a perspective view of a drafting table according to the
present invention when the drafting board is tilted at an angle of
several degrees to the horizontal.
FIG. 2 is an enlarged side view of the drafting table according to
FIG. 1; the dashed lines outline the position of the brace in an
alternate embodiment of the present invention.
FIG. 3 is an enlarged side view of the drafting table according to
FIG. 1 when the drafting board is tilted generally downwardly and
the brace is secured in a position for transport.
FIG. 4 is an enlarged fragmentary cross-sectional view taken on
line IV--IV through the pivotal joint between the support arm and
the vertical support member in FIG. 2.
FIG. 5 is an enlarged fragmentary cross-sectional view taken on
line V--V through the brace in FIG. 2.
FIG. 6 is an enlarged fragmentary cross-sectional view taken on
line VI--VI through the front portion of a drawer and the drafting
board in FIG. 1.
FIG. 7 is an enlarged fragmentary cross-sectional view taken on
line VII--VII through the rear portion of a drawer and the drafting
board in FIG. 1.
FIG. 8 is an enlarged fragmentary cross-sectional view taken on
line VIII--VIII through a two-drawer support arm in FIG. 1.
FIG. 9 is an enlarged bottom plan view taken on line IX--IX through
the vertical support members in FIG. 1.
FIG. 10 is a perspective view of a further embodiment of the
present invention in which the length of the vertical support
members is adjustable.
Like reference characters indicate corresponding parts throughout
the several views of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the drawings, a drafting table 10 according to the present
invention comprises a board 11 beneath which are suspended drawers
12 and 13 as described hereinbelow. The board 11, except those
portions thereof which are in close proximity to its periphery, is
preferably made of a lightweight material of sandwich-type
construction having thin faces 41, 42 of hardwood separated by a
core structure 43 formed of corrugated fiberboard or the like
(FIGS. 4-7). The board 11 is preferably full-size, the dimensions
thereof measuring, by way of example, approximately 36 inches by 60
inches.
A so-called hollow-core door may be utilized to form the board 11,
the peripheral regions of the board 11 having solid wood blocks
61-63 which are inserted between the thin upper and lower faces 41
and 42 as illustrated in FIGS. 4-8. The wood block 61 is
sufficiently wide to support such items as a drafting machine and a
lamp (not shown) when they are clamped to the upper edge of the
board 11. Alternately, the wood blocks 61-63 provide support for a
drafting machine utilizing pulleys (not shown) which are secured to
the underside of the board 11.
As is illustrated in FIGS. 1, 4-7, and 9, the periphery of the
board 11 has four sections of molding 34-37 attached, preferably by
glue, thereto. The molding is approximately 1/4th inch thick, made
of a hardwood such as sandalwood or the like, and is glued to the
remainder of the board 11. The molding sections 34-37 provide wear
resistance for the board 11. In addition, the molding sections
35-37 extend upwardly a distance of approximately 1/16th inch above
the proximate upper surface of the board 11. The molding section 34
also extends upwardly but a greater distance so that a catcher 34a,
as described hereinbelow, is formed.
When placed atop the board 11 within the raised sides of the
molding sections 34-37, the upper surface of a vinyl cover sheet 20
is flush with the upper surfaces of the sections 35-37 (FIGS. 4, 5,
and 7). A router can be used to machine the sections 35-37 to
create a smooth transition between them and the sheet 20. Such a
transition between the upper surfaces of the molding sections 35-37
and the sheet 20 helps to eliminate the possibility that any one of
its corners will become snagged by one of the drafting instruments
and inadvertently lifted from the board 11 with a concomitant
disruption of the draftsperson's work.
In contrast, the molding section 34, secured to the front edge of
the board 11, extends upwardly a distance substantially greater
than the thickness of the vinyl cover sheet 20 for substantially
the entire length thereof (FIGS. 1 and 6). The upwardly projecting
catcher portion 34a of the molding section 34 comprises a means for
catching drafting implements such as pencils, lead holders, and
inking pens (not shown) which have a tendency to roll downwardly
across the surface of the board 11 and which, in the absence of the
catcher 34a, would fall from the board 11.
As is illustrated in FIGS. 4, 7-9, support arms 14-16 and a cross
member 17 comprise a yoke 18 which is glued to the underside of the
board 11. The cross member 17 is rigidly attached to one end of
each of the support arms 14-16. The yoke 18 reinforces the board 11
and provides a structure to which a pair of vertical support
members 19, 19' can be secured. The yoke also supports the drawers
12, 13 which are insertable into the openings formed between the
leading edges 14a and 16a, 15a and 16a, respectively (FIG. 9).
The support arms 14-16 are braced laterally by reinforcing stays
44-46 (FIGS. 4, 5, 8, 9), each of the stays extending substantially
the entire length of the support arm along which it is juxtaposed
and to which it is secured by glue. The joint between each support
arm and the contiguous reinforcing stay is strengthened by
providing more than one plane within which each support arm and
stay is affixed to each other, thereby increasing both the contact
area of the joint as well as the magnitude of a shear force
required to cleave it. Thus under normal use, shear forces applied
to the joint will be dissipated through the support arm. As is
illustrated in FIGS. 4, 5, and 8, the upper corners of the rear
plates 12b, 13b of each drawer 12, 13 are cut away so that there is
sufficient clearance between the plates 12b, 13b and the stays
44-46 for the drawers 12, 13 to be slid along the keys 24-26, 26'
as described hereinbelow.
As is best seen in FIGS. 4, 8, and 9, keys 24 and 26 protrude from
opposing faces of the support arms 14 and 16 and are disposed
generally parallel to each other so that the pair of slots 22 and
22' which are formed on the sides of the drawer 12 as described
hereinbelow can be slidably engaged simultaneously with the keys 24
and 26, respectively. Likewise, the keys 25 and 26' protrude from
the support arms 15 and 16, the two-drawer support arm 16 having
two keys 26 and 26' which extend laterally from its sides to
suspend a drawer on either side of it. The pair of slots 23 and
23', described hereinbelow, can be slidably engaged with the keys
25 and 26', respectively. As is illustrated in FIGS. 4, 5, 8, and
9, each key 24-26, 26' comprises a wood insert, a portion of which
is fitted and glued within a groove formed in one of the support
arms 14-16.
As is seen in FIGS. 4-9, each of the drawers 12, 13 has slots 22,
22' and 23, 23', respectively, formed in each of the two sides
thereof. Each slot 22, 22' extends from the rear edge of the side
in which it is formed to the joint between that side and front
plate 12a of the drawer 12. Similarly, each slot 23, 23' extends
substantially the length of the side in which it is formed, the
slots 23, 23' terminating at the joint between that side and the
front plate 13a of the drawer 13.
A slight drag between each key and the slot with which it is
engaged prevents either drawer from opening under the force of
gravity alone when the drafting board 11 and the drawers 12, 13 are
tilted at an angle of several degrees to the horizontal and the
drawer is fully loaded. Drawer handles 60 may be provided to
facilitate opening the drawers 12, 13 (FIGS. 1, 6). Pairs of
cabinet door-type catches 40a, 40b, when interlocked, connect the
rear plates 12b, 13b with the blocks 40c, 40d attached to the
underside of the board 11 and are employed so that a fully-loaded
drawer can be maintained in a closed position when it is tilted
downwardly at a steep angle (FIG. 3). Alternately, the drawers 12,
13 may be maintained in a closed position by tilting them so that
the leading edges thereof are positioned upwardly. The drafting
table 10 can be folded rapidly into either position to form a unit
of narrow width to facilitate its transport.
The drawers 12, 13 are preferably of differing sizes with the
larger drawer 12 being used to store drawings and the smaller
drawer 13 to store drafting instruments. Alternately, a yoke with
only arms 14 and 15 to support a single drawer therebetween may be
provided. In a further modification of the yoke, two inner support
arms 16 may be provided between the outer support arms 14 and 15 so
that three drawers may be supported beneath the board 11. In each
of these modifications, the drafting board 11 covers each drawer
when it is closed. In such a compact arrangement, the clearance
between each drawer and the floor is ample for the movement of a
draftperson's legs.
As is best seen in FIG. 1, a pair of vertical support members 19,
19' extend generally downwardly from the underside of the board 11.
Each member 19, 19' is pivotally connected to one of the support
arms 14, 15 by a pin such as a carriage bolt 27 and a nut 28a
(FIGS. 1-4). The vertical support members 19, 19'; support arms 14,
15; and the washers 28b each have a hole formed therein for
receiving the bolts 27. A recess 24a, 25a in each of the keys 24,
25 communicates with the holes 14b and 15b, respectively (FIGS. 4
and 9). By forming a recess in each of the keys 24, 25 rather than
in the support arms 14, 15, there is still adequate material
present so that a larger bolt 27 can be utilized than would
otherwise be practicable. Thus a strong pivotal joint is provided
for a lightweight yoke 18.
One end portion of the brace 21, which is preferably formed of
steel, is also pinned to the support arm 14 (FIGS. 2 and 5). The
head of the bolt 38, which secures the brace 21 to the arm 14, is
recessed in the key 24 so that the bolt 38 does not interfere with
the motion of the drawer 12. The other end portion of the brace 21
is secured to the vertical support member 19 by the bolt 48. The
support arm 14, the vertical support member 19 and the brace 21,
when connected by the bolts 38 and 48, comprise a three-sided,
pinned structure of exceptional strength. A similar second
three-sided, pinned structure is formed by the support arm 15, the
vertical support member 19', and an additional brace 21. Together
with the yoke 18, this pair of lightweight, three-sided, pinned
structures forms a sturdy support for the board 11 and for the
weight of the upper portion of a draftsperson's body when rested
thereon. Moreover, because of the incorporation of such lightweight
structures and of the inclusion of sandwich-type construction
material in the board 11, the total weight of the drafting table 10
is much lighter than that of a conventional drafting table.
The angle of the board 11 to the horizontal can be adjusted by
varying the placement of the bolt 48 and of the nut 49 threaded
thereon. The bolt 48 can be inserted in any one of the four holes
51-54 which is formed within each of the vertical support members
19, 19'. The lowermost hole 54 is provided so that the board 11 can
be secured in a generally downwardly position (FIG. 3). With the
board 11 folded nearly parallel to the vertical support members 19,
19', the drafting table 10 can be moved readily from one room to
another or stored in a small space.
It is also possible to pin one end of the brace 21 to the member 19
with the bolt 48 inserted into the hole 51 and to connect the other
end of the brace 21 to the support arm 14 by a bolt 39' inserted
into the hole 39; the position of the brace 21 in this alternate
embodiment, in which the brace 21 is placed in tension rather than
in compression, is illustrated by the dashed lines in FIG. 2.
As is best seen in FIG. 1, a pair of vertical support members 19,
19' extend generally downwardly from the underside of the board 11,
the lower portion of each member 19, 19' being rigidly attached to
a base 30 having feet 31, 31'. The joint between each of the
members 19, 19' and the base 30 is a close-fitting one. The slot
into which the lower portion of the vertical support member 19, 19'
is inserted is preferably formed in the base 30 by dadoing to
obtain the required close tolerance. It is also preferred that the
lower portion of each vertical support member 19, 19' be secured to
each foot 31, 31' by glue but screws may also be utilized.
Each foot 31, 31' rests upon a pair of casters 32. The feet 31, 31'
also have notches formed therein into which a pair of foot rests
33, 33' can be inserted and secured to the feet 31, 31' by screws
(FIG. 1). As is also illustrated in FIG. 1, a kickboard 29 is held
in place between the vertical support members 19, 19' by removable
fasteners such as the screws 65 or the like. The kickboard 29,
which is similar in construction to the board 11, is preferably
made of a lightweight material having thin outer and inner faces of
3-ply plywood, each face consisting of hardwood veneers
approximately 1/8th inch thick; the faces are separated by a core
in the form of a honeycomb made of corrugated fiberboard or the
like.
In a further embodiment 70 illustrated in FIG. 10, each of the two
sections 57 and 58 overlap each other and are fastened together by
bolts 55 to form a first vertical support member 59. The member 59
and a second vertical support member (not shown) which, like the
member 59, has two sections 57 and 58 which overlap each other and
which are joined together by bolts 55 are employed to carry the
weight of the board 11. A plurality of holes 56 are provided in
each of the sections 57, 58; the average height of the board 11
above the floor can be adjusted by varying the placement of the
pairs of bolts 55 connecting each pair of sections 57 and 58. The
spacing between contiguous holes 56 in each of the sections 57, 58
is equal to facilitate the process of adjusting the height of the
board 11. The two overlapping sections 57 and 58 secured by the
bolts 55 inserted through the holes 56 comprise a means for
adjusting the length of each of the vertical support members.
Although several embodiments of the invention have been illustrated
in the accompanying drawings and described in the foregoing
detailed description, it will be understood that the invention is
not limited to the embodiments disclosed, but is capable of
numerous rearrangements, modifications, and substitutions without
departing from the scope of the invention.
* * * * *